untreated

adjective

un·​treat·​ed ˌən-ˈtrē-təd How to pronounce untreated (audio)
: not treated
untreated wastewater
especially : not improved or controlled medically
an untreated case of pneumonia
untreated diabetic patients

Examples of untreated in a Sentence

untreated wool
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Obstructive sleep apnea, or OSA, affects about 1 billion people globally, and 80% of people who have it are unaware and untreated, according to the American Medical Association. Matthew Glasser, ABC News, 30 June 2025 One of the most frequently responsible species for snakebites in the U.S., the rattlesnake's bites can be deadly if left untreated, especially for children and the elderly. Alice Gibbs, MSNBC Newsweek, 27 June 2025 If untreated, heat exhaustion can progress to heat stroke, potentially causing lasting damage to the brain, heart, kidneys, and muscles, according to the Mayo Clinic. Evan Moore, Charlotte Observer, 24 June 2025 Eagle is ready for a new family after healing from a severe leg injury that was left untreated, the San Diego County District Attorney’s Office said in a June 17 news release. Daniella Segura, Sacbee.com, 18 June 2025 See All Example Sentences for untreated

Word History

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of untreated was in the 15th century

Browse Nearby Words

Cite this Entry

“Untreated.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/untreated. Accessed 10 Jul. 2025.

Medical Definition

untreated

adjective
un·​treat·​ed -ˈtrēt-əd How to pronounce untreated (audio)
: not subjected to treatment
an untreated disease

More from Merriam-Webster on untreated

Last Updated: - Updated example sentences
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